Biomedical subjects

R Gal

Publications and source records attributed to R Gal.

At least 37 records · Page 2Linked to original sources

PubMed2000

[Progressive ptosis in children as a presenting sign of Kearns-Sayre syndrome].

Mitochondrial encephalopathies represent a heterogeneous group of various neurological syndromes caused by defects in mitochondrial metabolism. All clinical syndromes can be subdivided by type of biochemical defect into 3 subgroups: defective oxidation, defects in pyruvate metabolism and various defects in the respiratory chain. We present a 12-year-old girl admitted for evaluation of progressive ptosis over a period of 3 years, diagnosed as having the rare mitochondrial encephalopathy, Kearns-Sayre syndrome.

Blepharoptosis↗

PubMed2000

Overexpression of cyclin D1 mRNA in colorectal carcinomas and relationship to clinicopathological features: an in situ hybridization analysis.

Increased expression of a key cell cycle regulator, cyclin D1, may have relevance to carcinogenesis and clinicopathological characteristics of some cancers. This study represents the first application of in situ hybridization, ISH, to detect cyclin D1 mRNA in tissue sections from colorectal carcinomas. This approach was selected because of its unique potential to clarify whether increased expression of cyclin D1 mRNA correlates with clinical and pathological parameters. The ISH ofa non-radioactive oligonucleotide probe (Biogenex) was immunocytochemically detected in paraffin embedded sections from biopsy or resection specimens. Tumors ranged from well to poorly differentiated, and from stages A, B, C, and D. Ten year survival data were available on the majority of patients. Intensity of tumor and background (smooth muscle) signals were independently scored from 0 to 3. Overexpressed cyclin D1 mRNA was seen in 86% of cases compared to background. This frequency is similar to that reported for pancreatic carcinoma. The average signal intensity score in tumor foci was 1.9 with a background score of 0.05 (p<001). All cases showed specific staining judged by the cytoplasmic localization and a tumor signal:background ratio >1. Expression did not differentiate cancers based on grade, stage or survival (p>1), but did differentiate carcinoma and severe dysplasia from mild dysplasia. We conclude that ISH of cyclin D1 mRNA is an effective and relatively specific means of detecting activity of this gene in colonic neoplasms. The high frequency of overexpression implies that gene activity by itself is not likely to predict a tumor s biological or clinical behavior. On the other hand, these data suggest that increased cyclin D1 gene activity may be an early event in colorectal carcinogenesis. They also are consistent with findings showing cyclin D1 is inducible by a variety of oncogene products.

Adenocarcinoma↗

PubMed2000

Clinicopathologic study and classification of vocal cord cysts.

Cysts of the true vocal cords are less common than other laryngeal cysts. They are usually easily recognized and managed. Patients present with complaints of hoarseness and/or dyspnea. We report our experience with 41 cases of cysts located in the true vocal cords. Clinical and histological aspects are reviewed and discussed. A new histological classification is proposed: A: cysts lined by columnar epithelium with mucous content; B: lined by columnar epithelium with cilia; C: lined b squamous epithelium without keratinization; D: lined by squamous epithelium with keratinization.

Adult↗

PubMed2000

Pregnancy and amyloidosis: II. Suppression of amyloidogenesis during pregnancy.

The observation of a deleterious effect of pregnancy on kidney function in amyloidosis of familial Mediterranean fever suggests that pregnancy may enhance amyloidogenesis. To determine whether pregnancy may indeed affect amyloidogenesis, pregnant mice were made amyloidotic by administration of amyloid-enhancing factor (AEF) and AgNO3 at different points in time from conception, and amyloid- deposition was studied with the crush-and-smear technique. A possible effect of exogenous female sex hormones (beta-estradiol and progesterone) on amyloidogenesis was studied by administration of these hormones during amyloid induction in nonpregnant female mice. Amyloidogenesis was found to be significantly suppressed in mice during pregnancy. The reduction was possibly related to the effect of pregnancy on the inflammatory stimulus (AgNO3) and not on the administered AEF. Exogenous estrogen and progesterone failed to inhibit amyloidogenesis in nonpregnant mice. These findings suggest that pregnancy may suppress amyloidogenesis in mice. The suppression is caused by an anti-inflammatory effect of pregnancy. Estrogen and progesterone are probably unrelated to this finding.

Amyloidosis↗

PubMed2000

Differences in histochemical characteristics of gingival collagen after ER:YAG laser periodontal plastic surgery.

OBJECTIVE: The aim of this study is to evaluate gingival collagen for the effect of treatment with the Erbium:YAG Kesler handpiece. The handpiece is designed for gingival resurfacing in cases of hypertrophic gingiva and gingival pigmentation. BACKGROUND DATA: Lasers represent recent technological advances that afford new options for the treatment of periodontal diseases. However, lasers used for esthetic gingival soft tissue resurfacing require careful histopathological evaluation of the effects on tissue. In particular, it is important to determine the effect of laser irradiation on connective tissue, especially the collagen fibers. To date, no stage-wise clinical or histological studies have been performed addressing this issue. METHODS: Ten patients underwent irradiation with the following parameters: energy per pulse, 500 mJ; repetition rate, 10 pps; spot size, 3 mm. Gingival biopsy specimens were derived from 6 patients with hypertrophic gingiva and 4 with gingival pigmentation. The patients were examined before laser treatment and at 7 and 14 days after laser treatment. The tissues were fixed in tymph node revealing solution (LNRS), embedded in paraffin, sectioned at 5 microm, and stained with hematoxylin & eosin. The status of collagen in the treatment site was examined under polarized light after picrosirius red (PSR) staining. PSR is a collagen stain that differentiates collagen fiber density or size by means of a spectrum of color changes under polarized light. The major colors are red, orange, yellow, and green. RESULTS: We found a significant difference in the properties of collagen fibers at the first week and at 14 days post-treatment. In the normal gingiva, the predominant polarization colors were in the red-orange range, signifying tightly packed, mature collagen. During the first postoperative week, collagen fibers exhibited polarization colors in the green to green-yellow range, implying loosely packed collagen fibers. After 2 weeks, collagen fibers reacquired their preoperative PSR characteristics. CONCLUSIONS: We conclude that sequential series of changes accompany photothermal treatment of the gingiva. The occurrence of this sequence in all successful outcome cases may suggest the importance of these temporally sequenced changes in collagen during gum healing. In any event, the status of PSR staining of gum collagen provides a useful adjunct in the assessment of gingival health.

Adult↗

PubMed2000

The value of early and double phase 99Tcm-sestamibi scintimammography in the diagnosis of breast cancer.

The aim of this study was to assess the additional value of early and double phase scintimammography (SMM) with 99Tcm-sestamibi in the detection of breast cancer following initial evaluation by palpation and mammography. Altogether, 322 women with breast lesions evaluated prospectively by palpation, fine-needle aspiration and mammography were assigned a malignancy risk according to the results. Scintimammography was performed in all patients in the prone breast dependent position. Immediate and delayed views were obtained. Acquisition of immediate tracer uptake was termed 'early phase' SMM, whereas a combination of both immediate and delayed phase images was termed 'double phase' SMM. All patients underwent breast biopsy. Both early phase and double phase SMM detected eight of nine tumours in the low-risk group (88.8% sensitivity). In the uncertain cases (moderate-risk group), early phase SMM detected all malignant tumours, but double phase SMM missed one (92.3% sensitivity). In the high-risk group, early phase SMM missed two breast cancers (94.6% sensitivity) and double phase SMM missed four (89.2% sensitivity). Overall, early phase SMM had a sensitivity of 94.9% and a specificity of 80.2% in detecting breast cancer, whereas double phase SMM had a sensitivity of 89.8% and a specificity of 94.3%. Both methods had 100% sensitivity for tumours larger than 1 cm. In conclusion, SMM detected additional breast cancers following an initial evaluation by palpation, fine-needle aspiration and mammography. Our results suggest that double phase SMM is more specific than early phase SMM, although early phase SMM is more sensitive. Whether the interpretation of SMM results should rely on both early and delayed images, or early images alone, should be based on the relative risk of malignancy of the breast lesion as estimated by the initial evaluation.

Adult↗

PubMed2000

Protein kinase C (PKC) isoenzymes immunohistochemistry in lymph node revealing solution-fixed, paraffin-embedded bladder tumors.

Protein kinase C (PKC) plays an important role in cellular differentiation and in the malignant process. In an earlier study, it was shown that the expression pattern of PKC isoenzymes is altered in some tumors compared to their corresponding normal tissue. In this study, we evaluated the pattern of PKC isoenzyme immunostaining in bladder transitional cell carcinoma (TCC) of different grades and stages and normal tissue. Twenty-seven TCC samples and six areas of normal bladder mucosa were stained with antibodies specific for the PKC isoenzymes: alpha, beta 1, beta 2, delta, and zeta. The sections were scored for intensity of staining, and the correlation with grade and stage of the tumors was computed. The PKC alpha and beta 2 immunostains were intense in normal urothelium and in all evaluated tumors. PKC beta 1 and delta stains were intense in normal and low-grade and -stage tumors and weak in high-grade and -stage tumors. The opposite trend was found for PKC zeta. PKC isoenzyme expression differs in invasive TCC compared to low-grade, low-stage TCC and normal urothelium. The value of these findings as a marker of tumor aggressiveness should be further assessed.

Aged↗

PubMed2000

A comparison of two dose regimens in pancreatic cancer.

Forty-seven patients with pancreatic cancer were treated with two different schedules of 5-fluorouracil (5FU) and leucovorin (LCV): standard and dose-intense schedules. The standard regimen was monthly and the dose intense was biweekly. Partial response was observed in one patient (4%), no change in 12 (48%) and progression of disease in another 12 patients. Clinical benefit, measured by symptomatic improvement, was observed in 19% of all the patients, in 12% of those treated with the standard regimen and in 27% of the intense group. Median survival was 8 months for all the patients. The 1-year survival rate was 32%. Toxicity was mild. There was no survival benefit for the dose intense regimen. These results indicate that clinical benefit can be obtained with 5FU and LCV regimens despite the lack of objective response and that a dose-intense schedule is of little benefit in treating pancreatic cancer.

Adult↗

PubMed2000

Black thyroid adenoma. Clinical, histochemical, and ultrastructural features.

A 22-year-old woman with a "hot" thyroid nodule who was being treated with minocycline for severe acne vulgaris is presented. A partial thyroidectomy specimen revealed a black adenoma. Microscopically, the black pigment was found in the follicular cells and the colloid of the adenoma. The pigment was bleached with potassium permanganate and was Fontana-Masson stain positive. It was negative for iron, periodic acid-Schiff, and acid-fast Ziehl-Neelsen stains. All these feature suggest a melanin-like pigment. However, electron microscopic examination revealed a dense osmophilic material present within the lysosomes of the follicular cells. No melanosomes were present. Twenty-six previously reported cases are reviewed, and the possible mechanisms for the deposition of the pigment in the adenoma and its relation to minocycline degradation products are discussed.

Acne Vulgaris↗

PubMed1999

Colonic aberrant crypts may originate from impaired fissioning: relevance to increased risk of neoplasia.

Colonic aberrant crypt foci (ACF) can be identified on the unembedded mucosal surface as clusters of abnormal crypts with enlarged, surface opening. Because dysplasia is frequent, and may be a precursor of carcinoma, epithelial changes have been well studied. However, the basis for the distinctive changes in crypt architecture remain unclear. We hypothesized that some of the architectural alterations of aberrant crypts may reflect impaired fissioning during normal crypt duplication cycles. Fissioning begins at the crypt base. Using morphometric and immunocytochemical approaches, we examined 55 human ACF, both dysplastic and nondysplastic, for their architectural features. Non-ACF mucosa was compared. Microscopically, all lesions contained crypts that were attached, paired, dilated, and angulated. In 3 dimensions, these features related to multiple, individual complexes of connected crypts, referred to as connected crypt structures (CCSs). CCSs terminated in enlarged surface openings (2 to 5 x normal) which are morphometrically equivalent to the macroscopic aberrant crypts (P > .1). These openings trap marker dye. Support for an origin of CCSs in impaired basal fissioning is 3-fold. Crypt profiles in ACF are twice as frequent in basal mucosa as superficially (P < .001); in normal mucosa, the ratio is 1. In a CCS with vertically connected, co-planar crypts, the upper parent crypt diameter was the sum of diameters of inferiorly attached daughter crypts (P > .1). Proliferating cell marker, Ki-67, is not expressed at attachment points. In non-ACF mucosa, isolated CCSs consistently occur at foci of mechanical crypt distortion such as mucosal folds. We conclude that a CCS is a fundamental component of ACF of all histotypes. Impairment of normal crypt fissioning is probably a major factor in the histogenesis of CCSs, which often occurs in settings of mechanical distortion of the mucosa. The pathological significance of this process may be in the formation of enlarged crypt openings. The latter could trap dietary carcinogens as they trap dye, and thereby predispose the CCS to dysplasia.

Cell Division↗

PubMed1999

Lymph node revealing solution: a rapid method for the fixation of cystectomy specimens.

The objective of this study was to describe the use of the lymph node revealing solution (LNRS) for rapid fixation of total cystectomy specimens, and to compare it with formalin fixation. LNRS is a mixture of 95% ethanol, diethyl ether, glacial acetic acid and buffered formalin (65:20:5:10 v/v) prepared under a fume-hood. Sixteen consecutive cystectomy specimens were fixed for two hours either in LNRS or in buffered formalin. Representative sections were embedded in paraffin, sectioned and stained with H&E, periodic acid Schiff, alcian-blue, and immunostained for cytokeratins 20, high and low molecular weight cytokeratins, prostatic specific antigen, Factor VIII related antigen, s-100 protein, and protein kinase C isoenzymes. Results showed that the tissues were well fixed after 2 hours in LNRS, and were not fixed after 2 hours in formalin. Processing and sectioning of the paraffin blocks of the LNRS fixed tissue was excellent; it was impossible in the sections fixed for 2 hours in formalin. All the stains were excellent after LNRS fixation. We conclude that fixation of cystectomy specimens in LNRS requires only two hours and results in excellent stained slides. It is therefore recommended for cystectomy specimens.

Biomarkers, Tumor↗

PubMed1999

Bus commuters' coping strategies and anxiety from terrorism: an example of the Israeli experience.

This study examined the use of three coping strategies: (1) emotion-focused coping (calming-distraction); (2) problem-focused coping (checking-behavior); and (3) denial (reduced perceived vulnerability), and their relationship to anxiety from terrorism among 50 Israeli bus commuters. Their mean age was 31 years (60% females). Commuting frequency was negatively correlated, and problem-focused coping was positively correlated with anxiety from terrorism. Ratios of problem-focused coping/denial and of problem-focused/emotion-focused coping were each positively correlated with anxiety from terrorism. Coping ratios accounted for 15% of the variance in anxiety from terrorism, after considering commuting frequency. Combining minimal problem-focused preventative acts with distraction and reduced perceived vulnerability may be beneficial.

Adaptation, Psychological↗

PubMed1999

A new rapid technique for the fixation of thyroid gland surgical specimens.

One of the main diagnostic problems in thyroid pathology is to distinguish between follicular adenoma and follicular carcinoma. Thorough sampling of the nodule's capsule is recommended in order to identify capsular invasion. However, during the hardening of the tissue, by the usual fixatives the capsule shrinks and rolls downwards and sometimes the capsule separates from the remaining tissue. The present work evaluates the use of "Lymph Node Revealing Solution" (LNRS) for the rapid fixation (2h) of different thyroid lesions as compared to that of formalin. Fifty-one unselected consecutive cases of thyroid nodules, which included various benign and malignant lesions, were examined. Each specimen was cut in two equal parts; one was fixed in LNRS, the other in formalin. Fixation in LNRS for 2 hours gave adequate results in sectioning and staining of the tissue, and excellent immunostains. Its advantage over formalin is the conservation of the natural relationship between the capsule and the rest of the tissue, on the same plane, as well as the short time required for the final diagnosis.

Acetic Acid↗

PubMed1999

Three years of clinical evaluation of endodontically treated teeth by 15 F CO2 laser microprobe: in vivo study.

OBJECTIVE: Evaluation of the efficiency of 15 F CO2 laser microprobe, in cases of periapical lesions. The elimination of the pathological reaction caused by certain species of bacteria by reduction of reinfection and stimulation of osteogenesis. SUMMARY BACKGROUND DATA: Until now, no suitable delivery fiber existed for CO2 laser endodontic radiation in the apical region where it is most difficult to eliminate the pulp tissue using conventional methods. To overcome this problem, Sharplan Lasers designed a microprobe that reaches closer to the apex, distributing the energy density to a smaller area of the root canal, thus favorably increasing the thermal effects. METHODS: The study was conducted on 900 teeth, corresponding to 1512 root canals, divided in two groups. Four hundred sixty-eight were new cases, carefully selected according to strict parameters such as wide periapical translucency over 1 mm, supported by digital x-ray, with a lesion of 3 mm and more. All root canals were mechanically prepared in the conventional method up to size 35, Physiological saline solution served as rinsing solution and the root canals were treated by 15 F CO2 laser microprobe for 60 pulses repeatedly. The temperature at the surrounding tissue of the root did not exceed 38 degrees C. RESULTS: Filling of the canal was possible at the same appointment, without antibiotic treatment. Four hundred thirty-two of the cases, which were referred to us by other dentists after an unsuccessful treatment according to the classic therapy, were treated by the same laser therapy. Follow-up was performed by clinical examination, and a digital x-ray was taken, during and after treatment as well as after 3, 6, 9, and 12 months. CONCLUSIONS: There is a 98% success rate in both study groups, according to objective criteria for successful treatment including reduction of apical translucency after 2-6 months, freedom from clinical complaints, and no need for periapical surgery.

Humans↗

PubMed1999

Double-phase 99mTc-sestamibi scintimammography and trans-scan in diagnosing breast cancer.

UNLABELLED: The goal of our study was to assess the value of both scintimammography with 99mTc-sestamibi (SMM) and trans-scan (T-scan) in detecting breast cancer. METHODS: A total of 121 women were evaluated by palpation, mammography, SMM and T-scan. SMM was performed in the prone, breast dependent position. Immediate and delayed views (double-phase) were obtained. T-scan is a new breast imaging method that maps noninvasively the distribution of tissue electrical impedance and capacitance. RESULTS: SMM had 88.9% sensitivity, 88.4% specificity and 88.4% accuracy in detecting breast cancer. SMM had 100% sensitivity in detecting breast tumors >1 cm and only 66% sensitivity in detecting tumors <1 cm. T-scan had 72.2% sensitivity and 67% specificity in detecting breast cancer. It detected one more breast cancer than SMM, at the expense of 27 additional false-positive results. CONCLUSION: Double-phase SMM was sensitive and specific in detecting breast cancer. This method may reduce the rate of negative breast biopsies in tumors >1 cm. T-scan was only moderately accurate in detecting breast cancer. Its addition to SMM did not improve significantly the rate of breast cancer detection. However, because of its complete noninvasiveness, large-scale applicability and low cost, T-scan deserves further refining.

Adult↗

PubMed1998

Echocardiography in the diagnostic evaluation of syncope.

To assess the role of echocardiography in patients with syncope, we studied 439 consecutive adults who were referred over a 7-year period. Of all patients, 251 (57.2%) were women, who were generally younger than male referrals. All 439 patients had interpretable echocardiographic studies. Results showed that of patients younger than 40 years of age, 72.8% had scans that were normal and 18.5% had mitral valve prolapse (MVP). All (other) patients in this age group with abnormal echocardiographic findings (8.7%) had either abnormal physical findings over the heart, an abnormal electrocardiogram, or an abnormal chest radiograph. In patients 60 years old and older, 29.6% had scans interpreted as normal and 4.6% had MVP (approximately half of these patients had at least moderate mitral regurgitation). The study demonstrates that patients younger than 40 years of age with syncope are likely to have a normal Doppler echocardiography or MVP without significant mitral regurgitation. Thus additional abnormal findings (e.g., heart murmur, abnormal electrocardiogram, or abnormal chest radiograph) may be needed before the patient is referred to the echocardiography laboratory.

Adolescent↗

PubMed1998

Histological changes induced by CO2 laser microprobe specially designed for root canal sterilization: in vivo study.

OBJECTIVE: Until now, no suitable delivery fiber has existed for CO2 laser endodontic radiation in the apical region, where it is most difficult to eliminate the pulp tissue using conventional methods. To overcome this problem, we have designed a microprobe that reaches closer to the apex, distributing the energy density to a smaller area of the root canal and thus favorably increasing the thermal effects. METHODS: A CO2 laser microprobe coupled onto a special hand piece was attached to the delivery fiber of a Sharplan 15-F CO2 laser. The study was conducted on 30 vital maxillary or mandibulary, central, lateral, or premolar teeth destined for extraction due to periodontal problems. Twenty were experimentally treated with pulsed CO2 laser delivered by this newly developed fiber after conventional root canal preparation. Temperature measured at three points on the root surface during laser treatment did not exceed 38 degrees C. Ten teeth represented the control group, in which only root canal preparation was performed in the conventional method. RESULTS: Histological examination of the laser-treated teeth showed coagulation necrosis and vacuolization of the remaining pulp tissue in the root canal periphery. Primary and secondary dentin appeared normal in all cases treated with 15-F CO2 laser. Gram stain and bacteriologic examination revealed complete sterilization. These results demonstrate the unique capabilities of this special microprobe in sterilization of the root canal, with no thermal damage to the surrounding tissue. CONCLUSIONS: The combination of classical root canal preparation with CO2 laser irradiation using this special microprobe before closing the canal can drastically change the quality of root canal fillings.

Bacteriological Techniques↗

PubMed1998

Oropharyngeal fatty infiltration in obstructive sleep apnea patients: a histologic study.

It has been suggested that due to fatty infiltration, obstructive sleep apnea (OSA) patients have a narrower pharyngeal airway than normal persons. To identify potential fatty infiltration of pharyngeal tissues that may contribute to OSA, a histologic study of the distal soft palate was performed. Histologic sections of 46 oropharyngeal specimens were evaluated. This included 25 overweight OSA patients (25/31), 6 normal-weight OSA patients (6/31), and a control group of 15 healthy (non-OSA) individuals. A semiquantitative analysis of the fatty tissue was performed. In all 31 OSA patients an excess of fatty infiltration was found in the histologic oropharyngeal specimens in comparison to the control group. No correlation was found between the pharyngeal fatty infiltration degree, the body mass index, and the apnea index. Irrespective of their body weight, in none of the patients without OSA was excessive fatty infiltration seen. It is suggested that excessive pharyngeal fatty infiltration plays a role in upper airway obstruction in OSA and that it can be associated with the development of apnea.

Adipose Tissue↗